The knot transfer instrument of the present invention is designed to deliver more than one extracorporeally tied knot, one at a time, into the body cavity in laparoscopic surgery achieving effective ligation of tissues or vessels in a similar manner to that achieved in conventional surgery.
With more and more procedures being performed with the laparoscopic method, there is a great need for an instrument that will allow the surgeon to tie multiple knots in securing ligation or approximation of tissues inside a body cavity in a manner similar to that achieved in conventional surgery. There is no prior art that allows the application of multiple knots with extracorporeal knot tying in endoscopic surgery. At the present time, there are two methods of tying knots in endoscopic surgery: a) Intracorporeal knot tying and b) Extracoporeal knot tying.
a) Intracorporeal knot tying. This method involves instrument tying and is accomplished by holding the one side (limb) of the thread with one instrument, looping said thread over a second instrument, which second instrument then grasps the other side (limb) of the thread and by a withdrawing motion passes it through the loop and accomplishes the formation of a knot which is then brought down to the tissues to be ligated or approximated. By repeating the steps, multiple knots can be thrown as in conventional surgery. This method of intracorporeal knot tying is very cumbersome, time consuming and is inadequate for the surgeons currently performing endoscopic surgery.
b) Extracorporeal knot tying. Currently, there is a method of extracorporeal knot tying which involves the throw of a single compound knot (Roeder's Knot), which may or may not be preformed. The preformed knot is a part of a system commonly called endoloop and involves the formation of a loop by the creation of a single compound knot (Roeder's Knot) on the end of a thread. The other side of the thread passes through the center of a rigid rod and is firmly attached to the end portion of this rigid rod. The part of the rod through which the thread is passed can be broken off the part which is firmly attached to the thread. The way that this loop with the knot is used to ligate tissue is as follows. The loop with the rod is advanced into the abdominal cavity through a standard port. A grasper forceps is passed through the loop and is used to grasp the tissue to be ligated which it pulls through the loop. The intermediate part of the rigid rod is then broken off the top part of the rigid rod and advanced over the thread to the knot while the thread is pulled in the opposite direction with the top part of the rod. The intermediate part of the rod then positions the knot over the tissue to be ligated until the loop is closed thereover. The rod is then withdrawn from the abdominal cavity and the thread cut.
The non-preformed knot (Endosuture) is a system which is identical with the endoloop system except for the fact that there is a needle at the end of the thread and there is no knot or loop. The way that this system is used is as follows. The needle is advanced into the abdominal cavity with a needle holder and then passed through and/or around the tissue to be ligated and again withdrawn from the abdominal cavity. The needle is then cut off and a fisherman's knot is tied, thus forming a loop. Following the same steps as with the endoloop the knot is then advanced to the tissue to be ligated and the loop closed over said tissue to complete the operation.
The present invention represents an enormous advance in endoscopic surgery. Using the instrument and technique disclosed herein it is possible to rapidly tie knots extracorporeally and immediately transfer the knots internally to the tissue being ligated. A plurality of knots may be transfered intracorporeally expeditiously with the same ease as conventional surgery.